JP2002350406A - Eddy current test equipment - Google Patents
Eddy current test equipmentInfo
- Publication number
- JP2002350406A JP2002350406A JP2001158948A JP2001158948A JP2002350406A JP 2002350406 A JP2002350406 A JP 2002350406A JP 2001158948 A JP2001158948 A JP 2001158948A JP 2001158948 A JP2001158948 A JP 2001158948A JP 2002350406 A JP2002350406 A JP 2002350406A
- Authority
- JP
- Japan
- Prior art keywords
- defect
- circuit
- signal
- eddy current
- depth
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
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- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、渦流探傷装置に係
わり、特に鋼管表面の欠陥が従来より精度良く検出でき
る渦流探傷装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eddy current flaw detector, and more particularly to an eddy current flaw detector capable of detecting defects on the surface of a steel pipe with higher accuracy than before.
【０００２】[0002]
【従来の技術】金属等の導体に交流を流したコイルを近
づけると、該金属等に存在する欠陥（例えば、表面傷
等）は、該コイルに誘起される電流、電圧の変化として
検出される。また、必要ならば、金属の材料判別、膜厚
測定、形状・寸法等も測定できる。この原理を利用した
欠陥検出装置は、渦流探傷装置と称され、高速検出が可
能で、且つ検出結果を電気信号で取り出せるので、鉄鋼
においては棒鋼、線材、鋼管等の表面欠陥の検査に広く
利用されている。なお、上記コイルには、鋼管、線材等
の被検査体を囲む貫通方式、被検査体に単に接近させる
プローブ方式及び被検査体の内部に入れる内挿式のもの
がある。かかる渦流探傷器の基本的構成をフローで図２
に示すが、それは、発振器で作られた交流がコイルに流
され、交流磁場を被検査体（例えば、鋼管）に与えられ
るようになっている。そして、被検査体に生じた渦電流
をコイルが検出し、その出力を平衡回路に送る。また、
この探傷装置では、非常に小さな電流の変化分を検出し
なければならないので、前もって平衡回路は無欠陥の場
合の出力が０になるように調整しておく。この平衡回路
からの出力信号は、増幅器で増幅され、検波器に送られ
る（図２の装置では、信号波形のＸ軸、Ｙ軸の位相を別
々に処理できるよう、２つの検波器が設けられてい
る）。これら検波器は、その入力信号を移相器から加え
られる制御信号によって位相解析を行い、フィルタで欠
陥信号以外の雑音を除去し、被検査体からの情報をＣＲ
Ｔ（ブラウン管）等に表示する。さらに、フィルタを経
た信号は、最終的に欠陥判定回路に入力され、予め設定
されている判定条件と比較されて欠陥の有無が判定さ
れ、比較器から出力される。なお、上記欠陥判定回路
は、図３に示すように、位相角（θ＝ｔａｎ-１ｙ／
ｘ）検出回路、振幅（Ａ＝√（ｘ２＋ｙ２））算出回路
及び比較器で形成されている。なお、検出された信号
は、ブラウン管上では、図４に示すような位相角θ及び
振幅Ａを有する波形で表される。2. Description of the Related Art When a coil in which an alternating current flows is brought close to a conductor such as a metal, a defect (for example, a surface flaw) existing in the metal or the like is detected as a change in current or voltage induced in the coil. . Further, if necessary, it is possible to determine the material of the metal, measure the film thickness, measure the shape and dimensions, and the like. A defect detection device using this principle is called an eddy current flaw detection device, which can perform high-speed detection and can extract the detection result by an electric signal. Have been. The coils include a penetration type surrounding a test object such as a steel pipe and a wire rod, a probe method simply approaching the test object, and an insertion type inserted inside the test object. FIG. 2 is a flow chart showing the basic configuration of such an eddy current flaw detector.
As shown in Fig. 5, an alternating current generated by an oscillator is supplied to a coil, and an alternating magnetic field is applied to a test object (for example, a steel pipe). Then, the coil detects an eddy current generated in the object to be inspected, and sends its output to a balance circuit. Also,
In this flaw detector, since a very small change in current must be detected, the balance circuit is adjusted in advance so that the output when there is no defect is zero. The output signal from this balanced circuit is amplified by an amplifier and sent to a detector. (In the apparatus of FIG. 2, two detectors are provided so that the X-axis and Y-axis phases of the signal waveform can be separately processed. ing). In these detectors, the input signal is subjected to phase analysis by a control signal applied from a phase shifter, noise other than a defect signal is removed by a filter, and information from the device under test is converted to a CR.
It is displayed on T (CRT) or the like. Further, the signal that has passed through the filter is finally input to a defect determination circuit, is compared with a predetermined determination condition to determine the presence or absence of a defect, and is output from the comparator. In addition, as shown in FIG. 3, the defect determination circuit performs the phase angle (θ = tan- 1 y /
x) It is composed of a detection circuit, an amplitude (A = √ (x 2 + y 2 )) calculation circuit, and a comparator. The detected signal is represented by a waveform having a phase angle θ and an amplitude A as shown in FIG.
【０００３】ところで、この渦流探傷装置を実際に使用
して鋼管の表面欠陥を検出するには、ある大きさの人工
欠陥を用いて得た信号波形の位相角及び振幅を閾値とし
て予め欠陥判定回路に設定し、実際の被検査体より得た
信号の位相角と比較したり、あるいは該信号の算出され
た振幅Ａと比較して、欠陥の有無を判定するのが一般的
である。つまり、位相角又は振幅のどちらか一方で判定
し、しかも閾値の値は一点で固定されたものであった。In order to detect a surface defect of a steel pipe by actually using the eddy current flaw detection apparatus, a defect determination circuit is previously set using a phase angle and an amplitude of a signal waveform obtained by using a certain size artificial defect as a threshold value. In general, the presence or absence of a defect is determined by comparing with a phase angle of a signal obtained from an actual inspection object or by comparing with a calculated amplitude A of the signal. That is, the determination is made based on either the phase angle or the amplitude, and the threshold value is fixed at one point.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、上記位
相角設定による欠陥判定の場合、欠陥の深さの変化で位
相角が変化すると、その欠陥を検出できないことがあ
る。また、信号の振幅設定による欠陥判定の場合、該振
幅は欠陥の長さやコイルの大きさによって変化するの
で、その影響を受けて欠陥が検出できなかったり、実際
に欠陥でないものを欠陥として検出してしまうことがあ
る。つまり、欠陥の種類や大きさによって、見逃しや誤
認が生じる。これでは、渦流探傷装置を欠陥判定に信頼
して利用できず、まだ改善の余地が残されている。However, in the above-described defect determination by setting the phase angle, if the phase angle changes due to a change in the depth of the defect, the defect may not be detected. Further, in the case of defect determination by setting the signal amplitude, the amplitude varies depending on the length of the defect and the size of the coil. Sometimes. In other words, oversight or misidentification occurs depending on the type and size of the defect. In this case, the eddy current flaw detector cannot be used reliably for defect determination, and there is still room for improvement.
【０００５】本発明は、かかる事情に鑑み、被検査体の
欠陥を従来より精度良く、確実に検出可能な渦流探傷装
置を提供することを目的としている。The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an eddy current flaw detector capable of detecting a defect of an object to be inspected more accurately and more reliably than before.
【０００６】[0006]
【課題を解決するための手段】発明者は、上記目的を達
成するため鋭意研究し、その成果を本発明に具現化し
た。すなわち、本発明は、交流の発振器と、交流磁場を
被検査体に与え、発生した渦電流を検出するコイルと、
被検査体の無欠陥時の出力が０になるように調整する平
衡回路と、該平衡回路からの出力を増幅する増幅器と、
増幅された信号を移相器からの制御信号で位相解析する
検波器と、欠陥信号以外の雑音を抑制するフィルタと、
フィルタを経た信号が入力され、予め設定されている判
定条件と比較して欠陥の有無を判定する比較器、位相角
検出回路及び振幅算出回路からなる欠陥判定回路とを備
えた渦流探傷装置において、前記欠陥判定回路に、予め
定めた位相角と欠陥深さとの関係を記憶し、欠陥検出時
の位相信号により欠陥深さを定める欠陥深さ検出回路
と、予め設定した欠陥長さと振幅との関係を基に、前記
で定めた欠陥深さで該欠陥の判定基準値を計算する欠陥
判定基準値算出回路とを設けたことを特徴とする渦流探
傷装置である。この場合、前記フィルタと欠陥判定回路
との間に、フィルタからの出力を外部表示するＣＲＴを
設けたり、あるいは前記欠陥判定基準値算出回路の下流
側に、該算出回路からの出力の表示及び記録装置を備え
るのが良い。また、前記被検査体が鋼管であることが好
ましい。Means for Solving the Problems The inventor conducted intensive research to achieve the above object, and embodied the results in the present invention. That is, the present invention provides an AC oscillator, a coil for applying an AC magnetic field to a test object, and detecting the generated eddy current,
A balanced circuit that adjusts the output of the inspected object so that the defect-free output becomes zero, an amplifier that amplifies the output from the balanced circuit,
A detector for analyzing the phase of the amplified signal with a control signal from a phase shifter, and a filter for suppressing noise other than a defective signal,
An eddy current flaw detection device including a comparator that receives a signal that has passed through a filter and determines the presence or absence of a defect by comparing the signal with a predetermined determination condition, a defect determination circuit including a phase angle detection circuit and an amplitude calculation circuit, In the defect determination circuit, a relationship between a predetermined phase angle and a defect depth is stored, a defect depth detection circuit that determines a defect depth by a phase signal at the time of defect detection, and a relationship between a preset defect length and amplitude. And a defect judgment reference value calculation circuit for calculating a judgment reference value of the defect based on the defect depth determined above based on the above-mentioned. In this case, a CRT for externally displaying the output from the filter is provided between the filter and the defect determination circuit, or the display and recording of the output from the calculation circuit is provided downstream of the defect determination reference value calculation circuit. It is good to have a device. Preferably, the test object is a steel pipe.
【０００７】本発明によれば、欠陥深さの変化で信号の
位相角が変化したり、あるいは信号の振幅が欠陥の長さ
やコイルの大きさによって変化しても、それらの影響を
受けず、被検査体の欠陥を従来より精度良く、確実に検
出できるようになる。その結果、被検査体の欠陥検査に
要する時間や作業者の省力が達成され、該被検査体の生
産性が向上したばかりでなく、製造コストの削減も達成
できる。According to the present invention, even if the phase angle of the signal changes due to the change in the depth of the defect, or the amplitude of the signal changes according to the length of the defect or the size of the coil, they are not affected by the change. Defects of the object to be inspected can be more accurately and reliably detected than before. As a result, the time required for the defect inspection of the inspection object and the labor saving of the operator are achieved, and not only the productivity of the inspection object is improved but also the manufacturing cost can be reduced.
【０００８】[0008]
【発明の実施の形態】以下、図面を参照して本発明の実
施の形態を説明する。Embodiments of the present invention will be described below with reference to the drawings.
【０００９】まず、発明者は、欠陥の種類や大きさによ
って、見逃しや誤認が生じるという従来装置の問題点を
見直した。その結果、かかる問題が生じるのは、欠陥判
定装置に設定する位相角又は振幅の閾値をそれぞれ一点
だけで、しかも個別に欠陥の有無を判定することに原因
があると結論した。信号の位相角も振幅も同一欠陥から
生じたものであるので、両者の判定基準を同時に満足さ
せる必要があるからである。また、位相角や振幅は、欠
陥の深さや長さ等の値で変化するので、上記の判定基準
（閾値）も一点に固定したものではなく、欠陥の深さや
大きさに関係づけて定める必要があると考えた。そこ
で、発明者は、引き続き、これらの考えを具体化する手
段について鋭意研究を重ね、欠陥からの信号が位相角及
び振幅の両方の基準を満足する時に、その信号を発した
被検査体の部分に欠陥があると判定すると共に、振幅の
基準値を欠陥の深さや長さで変化させることにした。そ
して、図３に示した従来の欠陥判定回路を改造し、本発
明に係る渦流探傷装置とした。つまり、図１に示すよう
に、従来の欠陥判定回路へ、欠陥深さ検出回路及び欠陥
判定基準値算出回路を新しく設けるようにしたのであ
る。まず、本発明に係る渦流探傷装置は、従来の装置と
欠陥判定回路以外の部分は同じで良い。また、欠陥判定
回路も、（１）式で信号の位相を算出する位相角検出回
路と、（２）式で信号の振幅を算出する振幅算出回路
と、比較器とを備えている点は従来通りである。First, the inventor reviewed the problem of the conventional device that oversight and misidentification occur depending on the type and size of the defect. As a result, it has been concluded that such a problem arises because the phase angle or the amplitude threshold set in the defect determination apparatus is determined at only one point each, and the presence or absence of a defect is individually determined. This is because both the phase angle and the amplitude of the signal originate from the same defect, and therefore, it is necessary to satisfy both the criteria. In addition, since the phase angle and the amplitude change depending on values such as the depth and length of the defect, the above criterion (threshold) is not fixed to one point, but needs to be determined in relation to the depth and size of the defect. I thought there was. Therefore, the inventor has continued intensive studies on means for embodying these ideas, and when the signal from the defect satisfies both the phase angle and the amplitude criteria, the part of the test object that emitted the signal And that the reference value of the amplitude is changed according to the depth and length of the defect. Then, the conventional defect determination circuit shown in FIG. 3 was modified to provide an eddy current flaw detector according to the present invention. That is, as shown in FIG. 1, a defect depth detection circuit and a defect determination reference value calculation circuit are newly provided in the conventional defect determination circuit. First, the eddy current flaw detector according to the present invention may be the same as the conventional device except for the defect determination circuit. Further, the defect determination circuit conventionally includes a phase angle detection circuit that calculates the phase of the signal by equation (1), an amplitude calculation circuit that calculates the amplitude of the signal by equation (2), and a comparator. It is on the street.
【００１０】 θ＝ｔａｎ−１（ｙ／ｘ） （１） Ａ＝√（ｘ２＋ｙ２） （２） 本発明の重要なポイントの１つは、図１に示したよう
に、欠陥深さ検出回路を設けたことである。そして、こ
の欠陥深さ検出回路に、人工欠陥又は各種の自然欠陥を
用いて定めた欠陥の深さとそれにより生じる信号の位相
角との関係を設定しておくようにした。これにより、信
号の位相角が変化しても、その変化に応じて欠陥深さｄ
を求めることができるようにしたのである。Θ = tan −1 (y / x) (1) A = √ (x 2 + y 2 ) (2) One of the important points of the present invention is, as shown in FIG. That is, a detection circuit is provided. The relationship between the depth of a defect determined using an artificial defect or various natural defects and the phase angle of a signal generated by the defect is set in the defect depth detection circuit. As a result, even if the phase angle of the signal changes, the defect depth d depends on the change.
Was made possible.
【００１１】もう１つの重要ポイントは、図１に示した
欠陥判定基準値算出回路を設けたことである。そして、
この欠陥判定基準値算出回路には、上記同様に人工欠陥
又は自然欠陥を用いて別途求めた、欠陥深さをパラメー
タとした信号の振幅と欠陥長さとの関係を、予め記憶さ
せるようにした。このような回路を設けると、上記欠陥
深さ検出回路からの出力信号（欠陥深さがｄ＝ｄｏの時
の）に対応させて、振幅の判定基準値Ａｏを容易に定め
ることが可能となる。つまり、振幅の基準値を欠陥の深
さや長さで変化させるようにしたのである。Another important point is that the defect judgment reference value calculation circuit shown in FIG. 1 is provided. And
In this defect determination reference value calculation circuit, the relationship between the signal amplitude and the defect length using the defect depth as a parameter separately obtained using an artificial defect or a natural defect in the same manner as described above is stored in advance. By providing such a circuit, it is possible to easily determine the amplitude determination reference value Ao in accordance with the output signal from the defect depth detection circuit (when the defect depth is d = do). . That is, the reference value of the amplitude is changed depending on the depth and length of the defect.
【００１２】なお、比較器は、上記のようにして定めた
振幅の欠陥判定基準値Ａ０と測定で得た振幅値Ａとを比
較し、最終的な欠陥の有無を判定する。また、同時にラ
ンダムな位相を有する外来ノイズによる誤検出も防止で
きる。[0012] Incidentally, the comparator compares the amplitude value A obtained in the measurement and the defect determination reference value A 0 of the amplitude determined in the manner described above, determines the presence or absence of the final defect. At the same time, erroneous detection due to external noise having a random phase can be prevented.
【００１３】以下に、欠陥深さ検出回路及び欠陥判定基
準値算出回路の具体的な作用も含め、本発明に係る渦流
探傷装置の使用例を説明する。Hereinafter, an example of use of the eddy current flaw detector according to the present invention, including the specific operations of the defect depth detection circuit and the defect determination reference value calculation circuit, will be described.
【００１４】[0014]
【実施例】電縫鋼管からサイズが外径３４ｍｍ×肉厚
２．６ｍｍ×長さ３００ｍｍの試料を採取し、深さが５
水準で、各深さにつき幅及び長さを６水準変えて、人工
欠陥（この場合、ドリル傷及びノッチ傷とする）を加工
した。得られた人工傷を有する上記試料を本発明に係る
渦流探傷装置に通し、生じた信号の位相角と傷深さとの
関係、及び信号の振幅と傷長さとの関係を求めた。その
結果の一例を図５及び図６に示す。この図５及び図６の
関係は、それぞれ個別に、前記探傷装置の欠陥深さ検出
回路及び欠陥判定基準値算出回路に入力し、記憶させ
た。さらに、欠陥判定回路には、傷の判定基準値として
傷深さを０．３ｍｍ、傷長さを４ｍｍで設定し、記憶さ
せた。EXAMPLE A sample having an outer diameter of 34 mm, a wall thickness of 2.6 mm, and a length of 300 mm was collected from an ERW steel pipe and had a depth of 5 mm.
Artificial defects (in this case, drill and notch scratches) were machined by changing the level and width and length for each depth by six levels. The sample having the obtained artificial flaw was passed through the eddy current flaw detector according to the present invention, and the relation between the phase angle of the generated signal and the flaw depth and the relation between the signal amplitude and the flaw length were determined. One example of the result is shown in FIGS. 5 and 6 were individually input to and stored in the defect depth detection circuit and the defect determination reference value calculation circuit of the flaw detector. Further, in the defect determination circuit, a flaw depth was set at 0.3 mm and a flaw length was set at 4 mm as reference values for flaw determination, and stored.
【００１５】次に、実際に同一の電縫鋼管の製造ライン
に、上記の欠陥検出準備をした本発明に係る探傷装置を
セットし、傷の検出を開始した。その際、ある信号で振
幅が２５ｍｍ、θ＝６０°の場合があった。この信号
は、図５から明らかなように、欠陥深さ検出回路では、
傷深さｄが０．１ｍｍと定まる。また、図６より、欠陥
判定値算出回路では、傷長さが８ｍｍと算出される。従
って、欠陥判定回路の比較器からは、欠陥は存在しない
の出力が得られた。Next, the flaw detector according to the present invention prepared for the above-described defect detection was set on the same production line of the ERW steel pipe, and the flaw detection was started. At that time, there was a case where a certain signal had an amplitude of 25 mm and θ = 60 °. This signal is, as is apparent from FIG.
The scratch depth d is determined to be 0.1 mm. 6, the defect determination value calculation circuit calculates the flaw length to be 8 mm. Therefore, an output indicating that no defect exists was obtained from the comparator of the defect determination circuit.
【００１６】引き続き、別の信号をキャッチしたが、そ
の信号は、振幅が２２ｍｍと低かったが、位相角はθ＝
１４５°であった。この場合には、図５から明らかなよ
うに、欠陥深さ検出回路では、傷深さｄが０．３ｍｍと
定まる。また、図６より、欠陥判定値算出回路では、傷
長さが４ｍｍと算出される。従って、欠陥判定回路の比
較器からは、欠陥が存在するとの出力が得られた。Subsequently, another signal was caught, and the amplitude of the signal was as low as 22 mm, but the phase angle was θ =
145 °. In this case, as is clear from FIG. 5, the defect depth detection circuit determines the flaw depth d to be 0.3 mm. 6, the defect determination value calculation circuit calculates the flaw length to be 4 mm. Therefore, an output indicating that a defect exists was obtained from the comparator of the defect determination circuit.
【００１７】このことから、傷の長さによって振幅が変
化し、傷の深さによって位相角が変化しても、その両方
の情報と、予め事前データを利用して設定した判定基準
値とを使って、欠陥の正しい判定が可能であることが確
認できた。From this, even if the amplitude changes depending on the length of the flaw and the phase angle changes depending on the depth of the flaw, both information and a judgment reference value set in advance using advance data are determined. By using this, it was confirmed that correct judgment of defects was possible.
【００１８】なお、上記実施例は、本発明に係る渦流探
傷装置を電縫鋼管の欠陥検査に適用した場合であるが、
本発明に係る渦流探傷装置は、コイルの方式を変更し
て、電縫鋼管にかかわらず、棒鋼、線材、板材等の表面
や内面の欠陥検査に利用できることは説明するまでもな
い。In the above embodiment, the eddy current flaw detector according to the present invention is applied to a defect inspection of an electric resistance welded steel pipe.
It goes without saying that the eddy current flaw detector according to the present invention can be used for inspecting the surface and inner surface of bar steel, wire rod, plate, etc., regardless of the ERW steel pipe, by changing the coil system.
【００１９】[0019]
【発明の効果】以上述べたように、本発明により、被検
査体の欠陥を従来より精度良く、確実に検出できるよう
になる。その結果、被検査体の欠陥検査に要する時間や
作業者の省力が達成され、該検査体の生産性が向上する
ばかりでなく、製造コストの削減も達成できる。As described above, according to the present invention, the defect of the inspection object can be detected with higher accuracy and reliability than before. As a result, the time required for the defect inspection of the inspected object and the labor saving of the operator are achieved, and not only the productivity of the inspected object is improved but also the manufacturing cost can be reduced.
【図１】本発明に係る渦流探傷装置の欠陥判定回路の全
体を示すフロー図である。FIG. 1 is a flowchart showing an entire defect determination circuit of an eddy current inspection device according to the present invention.
【図２】従来の渦流探傷装置を示すフロー図である。FIG. 2 is a flowchart showing a conventional eddy current flaw detection device.
【図３】従来の渦流探傷装置の欠陥判定回路を示すフロ
ー図である。FIG. 3 is a flowchart showing a defect determination circuit of the conventional eddy current inspection device.
【図４】ＣＲＴ（ブラウン管）上に出現した欠陥に基づ
く信号の波形を示す図である。FIG. 4 is a diagram showing a waveform of a signal based on a defect that has appeared on a CRT (CRT).
【図５】信号の位相角と欠陥深さとの関係を示す図であ
る。FIG. 5 is a diagram illustrating a relationship between a phase angle of a signal and a defect depth.
【図６】信号の振幅と欠陥長さとの関係を示す図であ
る。FIG. 6 is a diagram showing a relationship between signal amplitude and defect length.
Claims (3)
与え、発生した渦電流を検出するコイルと、被検査体の
無欠陥時の出力が０になるように調整する平衡回路と、
該平衡回路からの出力を増幅する増幅器と、増幅された
信号を移相器からの制御信号で位相解析する検波器と、
欠陥信号以外の雑音を抑制するフィルタと、フィルタを
経た信号が入力され、予め設定されている判定条件と比
較して欠陥の有無を判定する比較器、位相角検出回路及
び振幅算出回路からなる欠陥判定回路とを備えた渦流探
傷装置において、 前記欠陥判定回路に、予め定めた位相角と欠陥深さとの
関係を記憶し、欠陥検出時の位相信号により欠陥深さを
定める欠陥深さ検出回路と、予め設定した欠陥長さと振
幅との関係を基に、前記で定めた欠陥深さで該欠陥の判
定基準値を計算する欠陥判定基準値算出回路とを設けた
ことを特徴とする渦流探傷装置。1. An AC oscillator, a coil for applying an AC magnetic field to a device under test and detecting the generated eddy current, and a balance circuit for adjusting the output of the device under test without any defect to zero.
An amplifier that amplifies the output from the balanced circuit, a detector that performs phase analysis on the amplified signal with a control signal from a phase shifter,
A filter that suppresses noise other than the defect signal, and a comparator that receives the filtered signal and compares the signal with a predetermined determination condition to determine whether there is a defect, a phase angle detection circuit, and an amplitude calculation circuit. In the eddy current flaw detection device including a determination circuit, the defect determination circuit stores a relationship between a predetermined phase angle and a defect depth, and a defect depth detection circuit that determines a defect depth by a phase signal at the time of defect detection. An eddy current flaw detection device, comprising: a defect determination reference value calculation circuit that calculates a determination reference value of the defect at the defect depth determined above based on a relationship between a predetermined defect length and amplitude. .
に、該算出回路からの出力の表示及び記録装置を備えた
ことを特徴とする請求項１記載の渦流探傷装置。2. The eddy current flaw detection device according to claim 1, further comprising a display and recording device for displaying an output from the calculation circuit downstream of the defect determination reference value calculation circuit.
する請求項１又は２記載の渦流探傷装置。3. The eddy current flaw detector according to claim 1, wherein the object to be inspected is a steel pipe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001158948A JP4715034B2 (en) | 2001-05-28 | 2001-05-28 | Eddy current flaw detector |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001158948A JP4715034B2 (en) | 2001-05-28 | 2001-05-28 | Eddy current flaw detector |
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|---|---|
| JP2002350406A true JP2002350406A (en) | 2002-12-04 |
| JP4715034B2 JP4715034B2 (en) | 2011-07-06 |
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ID=19002604
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001158948A Expired - Fee Related JP4715034B2 (en) | 2001-05-28 | 2001-05-28 | Eddy current flaw detector |
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| Country | Link |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006200913A (en) * | 2005-01-18 | 2006-08-03 | Tokyo Electric Power Services Co Ltd | Detector of thickness loss in hollow metal body |
| JP2006208312A (en) * | 2005-01-31 | 2006-08-10 | Jfe Steel Kk | Method and device for measuring internal defect |
| JP2007225564A (en) * | 2006-02-27 | 2007-09-06 | Mitsubishi Heavy Ind Ltd | Method and apparatus for evaluating eddy-current flaw detecting signal |
| JP2010025801A (en) * | 2008-07-22 | 2010-02-04 | Ihi Corp | Remote vortex flow flaw detector |
| JP2010054292A (en) * | 2008-08-27 | 2010-03-11 | Jfe Steel Corp | Method of measuring internal defect |
| JP2012037251A (en) * | 2010-08-03 | 2012-02-23 | East Japan Railway Co | Eddy current flaw detection method and eddy current flaw detector |
| KR101679520B1 (en) | 2015-12-02 | 2016-11-24 | 한국가스공사 | The defect's the width of a pipe measurement system using multi channel RFECT and measurement method using the same |
| KR102008105B1 (en) * | 2018-12-04 | 2019-08-07 | 에디웍스(주) | APPARATUS FOR DETECTING RAIL DEFECT BY USING MULTI-CHANNEL EDDY CURRENT SENSOR AND Sensor calibrating METHOD THEREOF AND RAIL DEFECT DETECTING METHOD |
| KR20190106305A (en) * | 2018-03-08 | 2019-09-18 | 주식회사 한국공업엔지니어링 | Contrast test specimens for measuring defects in tube expansion using eddy current test and method for measuring defects using the same |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63233363A (en) * | 1987-03-20 | 1988-09-29 | Sumitomo Metal Ind Ltd | Detecting method for flaw by eddy current |
| JPH01321355A (en) * | 1988-06-24 | 1989-12-27 | Nippon Steel Corp | Eddy current flaw detection method and apparatus |
| JPH04324353A (en) * | 1991-04-24 | 1992-11-13 | Tokyo Gas Co Ltd | Eddy current flaw detection method for piping |
| JPH05196608A (en) * | 1992-01-22 | 1993-08-06 | Osaka Gas Co Ltd | Separated eddy current flaw detecting method |
-
2001
- 2001-05-28 JP JP2001158948A patent/JP4715034B2/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63233363A (en) * | 1987-03-20 | 1988-09-29 | Sumitomo Metal Ind Ltd | Detecting method for flaw by eddy current |
| JPH01321355A (en) * | 1988-06-24 | 1989-12-27 | Nippon Steel Corp | Eddy current flaw detection method and apparatus |
| JPH04324353A (en) * | 1991-04-24 | 1992-11-13 | Tokyo Gas Co Ltd | Eddy current flaw detection method for piping |
| JPH05196608A (en) * | 1992-01-22 | 1993-08-06 | Osaka Gas Co Ltd | Separated eddy current flaw detecting method |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006200913A (en) * | 2005-01-18 | 2006-08-03 | Tokyo Electric Power Services Co Ltd | Detector of thickness loss in hollow metal body |
| JP2006208312A (en) * | 2005-01-31 | 2006-08-10 | Jfe Steel Kk | Method and device for measuring internal defect |
| JP4742600B2 (en) * | 2005-01-31 | 2011-08-10 | Ｊｆｅスチール株式会社 | Internal defect measurement method and apparatus |
| JP2007225564A (en) * | 2006-02-27 | 2007-09-06 | Mitsubishi Heavy Ind Ltd | Method and apparatus for evaluating eddy-current flaw detecting signal |
| JP2010025801A (en) * | 2008-07-22 | 2010-02-04 | Ihi Corp | Remote vortex flow flaw detector |
| JP2010054292A (en) * | 2008-08-27 | 2010-03-11 | Jfe Steel Corp | Method of measuring internal defect |
| JP2012037251A (en) * | 2010-08-03 | 2012-02-23 | East Japan Railway Co | Eddy current flaw detection method and eddy current flaw detector |
| KR101679520B1 (en) | 2015-12-02 | 2016-11-24 | 한국가스공사 | The defect's the width of a pipe measurement system using multi channel RFECT and measurement method using the same |
| KR20190106305A (en) * | 2018-03-08 | 2019-09-18 | 주식회사 한국공업엔지니어링 | Contrast test specimens for measuring defects in tube expansion using eddy current test and method for measuring defects using the same |
| KR102049524B1 (en) * | 2018-03-08 | 2020-01-08 | 주식회사 한국공업엔지니어링 | Contrast test specimens for measuring defects in tube expansion using eddy current test and method for measuring defects using the same |
| KR102008105B1 (en) * | 2018-12-04 | 2019-08-07 | 에디웍스(주) | APPARATUS FOR DETECTING RAIL DEFECT BY USING MULTI-CHANNEL EDDY CURRENT SENSOR AND Sensor calibrating METHOD THEREOF AND RAIL DEFECT DETECTING METHOD |
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